Hi there, based on your comment, I understand you want a more direct palette-row picker in the plugin UI, correct? Here is a workaround:
1. Right now, the palette has to be resized to fit exactly 4 colours per row first. That lets you see which row a selected indexed colour belongs to.
2. Turn the real-time guard on.
3. Pick or sample one colour from the row you want.
4. Click on the 8x8 tile you want to change.
5. The plugin will then reassign that whole tile to the 4-colour row that picked colour belongs to.
But it is indirect, because Aseprite only lets you pick one colour, not an entire row.